Cleaning the surfaces between adjacent teeth generally is a special problem outside the dental office. Those areas are not accessible to a tooth brush, yet they must be cleaned regularly. The consequence of not removing deposits there, especially on tooth surfaces inside the free gingiva, will very likely lead to diseases affecting teeth and periodontal tissues. The latter accounts for the large percentage of people who lose their natural teeth.
A cause of periodontal disease is initiated by bacteria acting on food particles deposited on tooth surfaces inside the gingival sulcus. The deposits become plaque which later harden as a result of calcium deposition. As additional debris accumulate, a sequence of biological, physical, and biochemical events occur which eventually lead to destruction of previously healthy tissues.
A cleaning method supplementary to brushing is therefore necessary. Good results have come from the use of dental floss or tape held and manipulated with the hands. Floss or tape tensioned within various types of frames which are manipulated with the hands can also produce positive results. However, these techniques require skill with considerable perserverance and are in the main, arduous and burdensome task.
Efforts to reduce the flossing burden have produced some complex devices that are patented. These include U.S. Pat. No. 3,534,745 which reveals a device that has dental tape spanned between two prongs which form a U-shape. The device moves the prongs such that the motion of the tape they hold generates a shape envisioned as two cones attached at their apices. Included in the device are supply and take-up reels disposed to provide replacement for the spanned tape increment by manual advancement when desired by the user.
U.S. Pat. No. 4,014,354 describes a device that holds a length of floss between two spaced L-shaped arms. The device reciprocates the arms and the floss in an arc about the axis of a handle to which one end of the arms are attached.
In the interests of comfort, neither of the above mentioned devices show means to protect the oral tissues from contact with the powered motion of the prongs or support arms. Nor can they automatically replace the used floss.
U.S. Pat. No. 3,667,483; U.S. Pat. No. 3,759,274; U.S. Pat. No. 3,847,167; U.S. Pat. No. 4,326,549 and U.S. Pat. No. 4,338,957 disclose devices that reciprocate floss or tape in only one dimension; in a transverse motion across the tooth surface. The vertical cleaning motion must be manually provided by the user.